All the other "emperors" are, as you can guess from their names, Germanic leaders (simple soldiers like Odoacer, or magnificient kings such as the OstrogothTheodoric the Great). They tried to preserve an imperial power in Rome, but they failed. The first real western emperor after Augustulus was the Frank king Charlemagne (official coronation by the Pope in 800 A.D.), who unified all of western Europe under his rule, thereby laying the foundation for virtually all of European history to date.

Note 1 : The german word "Kaiser" also comes from "Caesar".
Note 2 : All of this applies only to the western empire. The Byzantine Empire (395) managed to survive until Constantinople was taken by the Turks in 1453.

There is good reason to regard Julius Caesar as the first emperor, and he was so called throughout the Middle Ages, but the convention these days is that we start with Augustus as the first. With his reign the empire became continuous. See Princeps by Gone Jackal (and to a lesser extent my Roman Empire) for a more detailed discussion of the comparative powers and titles of Caesar and Augustus.

The names Caesar and Augustus, and the military title Imperator, all continued as part of the regnal titles of the emperors. (In the later period of the Tetrarchy the Caesar was deputy emperor to the Augustus.) Their full names and styles were often very complex; the names given here are the more familiar ones.

Where multiple emperors are given at the same time, there are three possible causes: (i) they were killed or overthrown in quick succession (e.g. the year 69); (ii) the emperor shared power with his son or other intended successor; or (iii) they were rivals appointed by troops in different parts of the empire. I have made some explanatory notes where I can work out what happened.

Diocletian and Maximian 286-305
Uh oh, now it gets complicated. This was the Tetrarchy with two Augusti as main emperors, east and west, and two Caesares as deputies. I've drawn myself some time-lines to try to work out which reigns overlapped. I am listing only the emperors and co-regents, not their deputies. Maximian, having abdicated with Diocletian in 305, actually resumed the title of Augustus in 307-308 and in 309-310, but if I try to fit him in down here you'll reach out of the chatterbox and throttle me till my eyes bug out, so let's not.

On the death of Theodosius the empire was permanently divided into independent states, the Western Roman Empire going to his son Honorius, and Eastern Roman Empire, better known as The Byzantine Empire, going to his son Arcadius. See under those two nodes for subsequent emperors.

Right, the above list is so confusing that here it is again in a more familiar form, one line per emperor; this means there's lots of overlapping dates. Refer to the above to resolve them; refer to this one below if you just want a simple list. (In case I made a mistake rearranging it, the one above is more accurate.)